content: /*
   * Copyright 2016 David Karnok
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package hu.akarnokd.agera;
  
  import android.support.annotation.NonNull;
  
  import com.google.android.agera.Observable;
  import com.google.android.agera.Updatable;
  
  /**
   * Skips the first N signals.
   */
  final class AgeraSkip extends AgeraSource<SkipUpdatable> {
      final long n;
  
      AgeraSkip(Observable source, long n) {
          super(source);
          this.n = n;
      }
  
      @NonNull
      @Override
      protected SkipUpdatable createWrapper(@NonNull Updatable updatable) {
          return new SkipUpdatable(updatable, n);
      }
  }
  
  final class SkipUpdatable implements Updatable {
      final Updatable actual;
      long remaining;
  
      SkipUpdatable(Updatable actual, long remaining) {
          this.actual = actual;
          this.remaining = remaining;
      }
  
      @Override
      public void update() {
          long r = remaining;
          if (r == 0L) {
              actual.update();
              return;
          }
          remaining = r - 1;
      }
  }
  